ex moved on so quick

My ex broke up with me saying our relationship “wasn’t working,” which already hurt a lot. But about two weeks after we ended things, I found out she started talking to another guy — and now he’s following her on all her social media. It just feels like everything moved on so fast, and it’s been really messing with my head.

What’s confusing me even more is that while we were still together, this same guy was trying to get her attention when she went out. She told me she felt uncomfortable, said what he was doing was wrong, rejected him, and even blocked him at the time. So now seeing her talk to him after we broke up is really hard to process.

I didn’t expect any of this, and it’s making me question everything — like whether what we had was even real or if I completely misread things. I keep overthinking how someone can move on that quickly.

Has anyone else gone through something like this? How do you deal with the confusion and the hurt without driving yourself crazy thinking about it all the time?